package com.CoreryBlack.filter;

import com.CoreryBlack.util.JwtUtils;
import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.apache.http.HttpStatus;
import org.springframework.util.StringUtils;

import java.io.IOException;

/**
 * @Description TokenFilter
 * @Author CoreryBlack
 * @Date 2024-09-22
 */

@Slf4j
@WebFilter(urlPatterns = "/*")
public class TokenFilter implements Filter {

    @Override
    public void doFilter(ServletRequest rep, ServletResponse resp, FilterChain chain) throws
            IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) rep;
        HttpServletResponse response = (HttpServletResponse) resp;
        //1.获取请求url
        String url = request.getRequestURL().toString();

        //2.判断请求url中是否包含login，如果包含，说明是登录操作，放行
        if (url.contains("login")) { //登录请求
            log.info("登录请求，直接放行");
            chain.doFilter(request, response);
            return;
        }

        //3.获取请求头中的令牌(token)
        String jwt = request.getHeader("token");

        //4.判断令牌是否存在，如果不存在，返回错误结果(未登录)
        if (!StringUtils.hasLength(jwt)){//jwt不存在
            log.info("获取到jwt令牌为空，返回错误结果");
            response.setStatus(HttpStatus.SC_UNAUTHORIZED);
            return;
        }

        //5.解析token.如果解析失败，返回错误结果（未登录）
        try {
            JwtUtils.parseJWT(jwt);
        }catch (Exception e) {
            e.printStackTrace();
            log.info("解析令牌失败，返回错误结果");
            response.setStatus(HttpStatus.SC_UNAUTHORIZED);
            return;
        }

        //6.放行
        log.info("令牌合法，放行");
        chain.doFilter(request, response);
    }
}
